1. Field of the Invention
The present invention relates to a thermoplastic elastomer which is excellent in profile extrudability, oil resistance, bonding properties and weather resistance and which is compatible with an olefinic material.
2. Discussion of Background
A thermoplastic elastomer is excellent in rubber elasticity, coloring properties and design latitude and can be formed by various forming methods such as injection molding, extrusion, blow molding, sheet forming and vacuum forming, like usual thermoplastic materials. Accordingly, it is used in various fields, e.g. as packing materials for automobiles and building materials, interior materials for automobiles, parts for building materials and sundry goods, and its use is rapidly expanding. Especially, an olefinic thermoplastic elastomer is light in weight, can easily be recycled and has a high cost performance, and thus, it has been used frequently in recent years. However, the olefinic thermoplastic elastomer has had a problem that during the extrusion, drawing is difficult as the melt tension is low, and it is particularly difficult to form a complicated shape by profile extrusion, whereby it has been difficult to obtain an extruded product excellent in the surface smoothness. The extruded product has had a problem that as the surface tension is low, the bonding property is poor, and even if the extruded product is bonded by means of a pressure sensitive adhesive double coated tape, it may easily be peeled. Further, the olefinic thermoplastic elastomer tends to swell against an oil such as a lubricating oil, a mineral oil, an engine oil or an animal or plant oil, and thus it has had a problem that it can not be used at a site where an oil may be applied. In such an application where oil resistance is required, a polyvinyl chloride type thermoplastic elastomer is used, but such an elastomer has had a problem that it is not compatible with an olefinic material. Under these circumstances, it has been desired to develop a material which is excellent in profile extrudability, oil resistance, bonding properties and weather resistance and which is compatible with an olefinic material.